Keyboard



FIG. 1 is a perspective view of a keyboard showing our new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a left side elevational view thereof;

FIG. 4 is a right side elevational view thereof; and,

FIG. 5 is a rear elevational view thereof.

The broken lines are shown in the views for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a keyboard, as shown and described. 